Loader machine



March 4, 1952 E. M. M ELHINNEY ETAL LOADER MACHINE 3 Sheets-Sheet 1Original Filed Dec. 13, 1946 IN V EN TOR. y; 1%

flow/ g 211 77. 97262712? Sic/F. i oc fi March 4, 1952 E. M. MOELHINNEYET AL 23,466

LOADER MACHINE Original Filed Dec. 13, 1946 5 Shets-Sheet 2 March 4,1952 M, McELl-NNEY ET AL Re. 23,466

LOADER MACHINE 3 Sheets-Sheet 3 Original Filed Dec. 13, 1946 ReissuedMar. 4, 1952 UNITED STATES FATENT OFFICE LOADER MACHINE Eric M.McElhinney, Bysart, and Theodore A. P-odhajshy, Traer, Iowa 7 8 Glaizns.31. 214-141) This invention relates generally to loader machines and inparticular to a loader attachment for a usual type farm tractor capableof handling manure, hay, dirt and the like.

An object of this invention is to provide I improved loader machine.

Another object of this invention is to provide a tractor loaderattachment which affords visibility to the tractor operator is ca ofelevating and positively holding a load -a carrying position closelyadjacent to the end of the tractor, and then moving load upwardly andforwardly of the tractor to a dumping position.

A further object of this invention is to a loader attachment for atractor having pivoted telescoping booms, in which the bcoms supportedadjacent their load carrying ends at all elevated and extended positionsthereof.

Another object of this invention is ts vide a loader attachment for atractor in which. a pair of pivoted booms having a load carryim -iiit attheir free ends, are supported at all elevated positions againstmovement sidewise or laterally of the tractor.

Still a further object of this invention is to provide a loaderattachment for a tractor lch is of a construction such that the weightof the attachment and any load carried thereby is applied on the tractorframe intermediate the front and rear wheels therefor.

Another object of this inventi-on'is to provide a loader attachment fora tractor which is of a compact and rugged construction, eflicient inhas a pair of forwardly extended lift members which are in a movablesupporting engagement at their front ends with the telescoping members.The lift frame is pivoted by tractor operated means to raise and lowerthe lift members, and includes a pair of rearwardly extended levers orarms which are connected with the telescop1ng members through a leversystem adapted to move the telescopin members in response to a pivotalmovement of the. lift frame.

Another feature of this invention. is found in the provision of atractor loader attachment having a pair of telescoping booms arranged atopposite sides of the tractor, and pivoted attheir ends on the tractor,in which a load carrying unit is mounted between the front ends ,oftelescoping members supported on the forward ends of the booms. Thebooms are raised and lowered by means including a pivoted lift frame,pivotally supported at its rear end at a position above and forwardlyfrom the pivots forthe boom and pivotally moved by tractor operatedmeans. A pair of forwardly extended lift members on the pivoted framemovably engage and the telescoping members, which are moved in responseto a pivotal movementof the lift frame by means incluing a pair of.rearwardly extended rock arms on. the lifting frame, a pair of uprightlevers pivoted at their lower ends the boom pivots, and links connectedbetween the reel: arms and upright levers, and between the uprightlevers and the telescoping members. The rock arms and upright levers arerelatively arranged so as to be in planes substantially normal to eachother when the booms are in a substantially horizontal position so thatthe telescoping members are in contracted positions durin movement ofthe booms between horizontal and lowermost positions therefor.

A further feature of this invention is found in the provision of atractor loader attachment. in which a pair of pivoted booms, with a loadcarrying unit between their front ends, are raised and lowered by apivoted lift frame assembled relative to the booms and to a pair of.hydrauliccylinders arranged at opposite sides of the tractor such thata high elevation of the booms is accomplished with a minimum of movementfor the lift pistons in the hydraulic cylinders.

Further objects, features and advantages of this invention will becomeapparent from the following description when taken in connection withthe accompanying drawings, in which:

Fig. l is a side elevational view of thetractor loader attachment ofthis invention in assembly relation with a usual farm tractor, withcertain parts being removed to more clearly showsuch assembly;

Fig. 2 is a plan view of the assembly shown in Fig. 1, with certainparts broken away for the purpose of clarity;

Fig. 3 is an enlarged sectional detail view. ,taken on the line 3-3 ofFig. 2;

Fig. 4 is a fragmentary perspective view of the scoop-latching mechanismFigs. 5 and 6 are enlarged sectional detail views as seen along thelines 5-5 and 6-6, respectively, in Fig. 1, with certain parts beingbroken away in Fig. 5;

Fig. 7 is an enlarged sectional detail view taken on the line 1-1 inFig. 6;

Fig. 8 is an enlarged sectional detail view taken on the line 8-8 inFig. 2; and

Fig. 9 is a fragmentary detail perspective view, with parts broken away,of a portion of a pivoted lifting frame which forms part of the loaderattachment of this invention.

With reference to the drawings, the loader attachment of this inventionis illustrated in Figs. 1 and 2 in assembly relation with a usual typefarm tractor having a frame I0, steering wheels .II and traction wheelsl3 mounted on a rear axle l4.

The attachment includes a pair of pivoted telescoping booms l6 havingrear members H of a box shape in cross section and front members l8 of achannel construction adapted for telescopic assembly within the rearmembers |1 (Figs. 2 and 3). The telescoping members I8 ing pairs ofrollers l9 rotatably supported in brackets 2| secured as by welding tothe top and bottom walls or sections 22 and 23, respectively, f the rearmembers H.

The walls 22 and 23 are cut away, as indicated at 24, to receive therollers |9 therethrough for riding engagement with the top and bottomsides of the front telescoping members I8.

The booms l6 are arranged at opposite sides of the tractor frame It] andare pivoted at their rear ends on the tractor rear axle l4 (Figs. 1 and6) by the provision of a pair of transversely spaced lugs 26 projectedrearwardly from the boom members [1 and adapted to receive therebetweena forwardly extended lug 21 mounted on the rear axle l4. Pivot bolts 28inserted within aligned openings formed in the lugs 26 and 21 pivotallysupport the booms l6 for up and down pivotal movement.

The forward ends of the booms l6 are connected together by a transversemember 29 of a channel construction (Figs. 2 and 4) which is welded atits opposite ends to the telescoping members I8. Suitable brace members3|! of a plate form are welded between the transverse channel member 29and the telescoping members l8. Pivotally supported at 3| (Figs. 1 and2) between the front ends of the telescoping members l8 and forwardly ofthe transverse connecting member 29 is a scoop or load carrying unit 32.

The booms l6 are raised and lowered by means including a lift frame,designated generally as 33 (Figs. 1 and 2) of a substantially invertedU-shape and transversely arranged in a straddling relation with thetractor frame Ill. The lift frame 33 is of a pipe construction and has atransverse pipe shaft 34 pivotally supported on the top of an uprighttransverse frame, indicated at 36, mounted on the tractor frame ID.

The upright frame 36 is located forwardly of the tractor rear axle I4and includes a pair of upright side frame members 31 of a channelconstruction (Fig. which are mounted opposite each other on bracketmembers 38 welded on the tractor frame Ill. The side frame members 31extend upwardly above the top level of the tractor engine hoodor cowl39, and are connected across 4 their upper ends by a transverse channelmember 4| which is faced upwardly. Brace members 42 are connectedbetween the side frame members 31 and the top transverse frame member4|.

The lower ends of the side frame members 31 terminate in rearwardly anddownwardly extended projections 43 (Fig. l) for a purpose to beexplained later. The upright frame 35 is supported against tippingmovement by brace members 44 connected between the tractor frame In andthe side frame members 31. r

The pipe shaft 34 of the lift frame 36, is rotatably supported withinthe upturned top transverse channel member 4| in bearings 46 (Fig. 5)located at opposite ends of the channel 4| and secured to the channel byU-clamps 41. The pipe shaft constitutes part of a transverse framestructure in the lift frame 36 which includes a second transverse pipemember 48 (Figs. 2 and 5) arranged forwardly of and in a spaced parallelrelation with the pipe shaft 34. These two transverse pipe members 34and 48 are connected together by braces 49 of a pipe construction.

Projected forwardly from opposite ends of the two transverse pipemembers 34 and 48 are pipe members 5| and 52, respectively (Figs. 1 and2), which are bent outwardly and then forwardly such that their frontends 53 and 54, respectively, are arranged side by side in a superposedparallel relation to provide for their being welded together. Bracemembers 56 are connected between the top pipe members 52 and thetransverse pipe member 48. The brace members 56 in turn are connectedtogether by a transverse pipe member 51a.

A pair of rods 55 (Figs. 1 and 8) are insertable to adjusted positionswithin the front ends of the pipe members 5| and 52 and are connectedtogether at their forward ends by platemembers 51. Extended downwardlyand forwardly from each plate member 51 is a pair of transversely spacedarms 58, of a flat bar construction, having rollers 59 rotatablysupported between their lower ends. As best appears in Figs. 1 and 2,the front telescoping members l8 of the booms l6 extend between the arms58 in supported positions on the rollers 59.

In order to adjust the rods 55 longitudinally of the pipe members 5| and52, a circular opening 6| (Fig. 8) is formed between the adjacent sidesof the pipe members 5| and 52 rearwardly from their front ends. Theadjacent inner sides of the rods 55 are formed with a series ofoppositely arranged axially spaced notches 62 of a semicircular shapecorresponding in size to the opening 6|. When a pair of opposite notches62 are positioned in alignment with the opening 6| a bolt 63 insertedtherethrough holds the rods 55 in adjusted positions against axialmovement relative to the pipe members 5| and 52.

On pivotal movement of the lift frame 33 the booms l6 are lowered andraised by virtue of their movable support on the rollers 59 at the frontends of the pipe members 5| and 52. It is seen, therefore, that eachassociated pair of pipe members 5| and 52 constitute a lift arm formedas part of the lift frame 33.

Pivotal movement of the lift frame 33 is accom plished by the provisionof a pair of hydraulic cylinders 64 (Figs. 1, 2 and 5) arranged atopposite sides of the tractor frame and pivotally supported at theirlower ends on a transverse shaft 66 supported at the lower or rear endof the extensions 43 of the upright side frame members 31. The cylinders84 are maintained in a spaced relation outwardly from adjacent uprightframe members 31 by collar or sleeve members 51 flowermost positions,the cylinders are substantially normal to the plane of the lift arms.Fluid I under pressure is supplied to the cylinders 64 from a usual typeoil pump unit (not shown) carried v on the tractor and operated thereby.

The telescoping members I8 are extended and contracted in response to apivotal movement of the lift frame 33 by the provision of meansincluding a pair of longitudinally extended angle plate members ll(Figs. 1. and 9) which have their front ends connected between the upperends of the pipe members 5| and 52 of the lift arms, and their rear ends12 projected rearwardly from the lift frame 33.

The rear ends 12 t us constitute rocker arms on the pipe member 34.Inserted within the ends of the pipe member 34 (Fig. 5) are plugs 13which have tapped holes in their outer ends to receive bolts 14 extendedthrou h the plates 1|. he pipe members 52 (Fig. 9) have lu s 16 on therear sides of their top ends adapted to receive bolts which areinsertable through the front ends of the plate arms I I.

A pair of upright le ers 11 (Figs. 2 and 6) have U-shaped lo er ends 18pivoted on the boom pivot 1 bolts 28 and arranged in a straddlingrelation with the lugs 26. Forwardly and downwardly extended lin s 19(Fig. l) have their front ends pivotally connected at 8! with thetelescoping members l8 and their rear ends pi otally connected at 82with t e upper ends of the upri ht levers H. Up ardly and for ardlyextended lin"s 83 have their front ends pivotally connected at 84 withthe free ends of the rock arms 12, and their rear ends 86 connected withthe levers ll, intermediate their ends. by a lost motion means indicatedgenerally as 81.

Since the construction and relative assembly of each lost motion means81 with a corres onding upri ht lever 11 is the same, onl one of suchassemblies will be referred to in the follo ing description. T e o t moton means 81 inc udes a collar mem er 88 (Fi s. 6 and '7) hav noppositelv arranged pi ots 89 supported in the lever 11 and in a brac"etmember 9! secured to and spaced. laterallv from t e inner side of thelever H. Slidablv inserted throu h the collar member 88 is a tubu arsleeve member 92 w ich is mounted about the threaded rear end 86 of thelink 83.

A first adiusting nut 93 is threadable on the rear end 86 of the link 83forwardly of the collar 88 and the sleeve 92. A coil spring 94 ismounted about the sleeve 92 and maintained in compression against therear side of the collar 88 by a second ad ustin'r nut 96 threa'lable ont e rear end 85 of the l n" 83 rear ardlv of the sleeve 92. By relativeadjustment of the nuts 93 and 98 the effective len th of the link 8'1!bet een the upright lever 11 and a roc arm 12 is varied, and the lostmotion of the link 83 in a rearward direction relative to the uprightlever 11 is adjusted.

In the operation of the loader machine of this invention, assume thatthe booms l6 are in their lo ermost positions as indicated in dottedlines at A in Fig. 1. At this position of the booms the pivotedconnection 8| of the front ends of the links 19 are adjacent to theforward ends of the rear boom members [1, and the pivoted lift frame 33is in a lowered position such that the lift arms, comprised of themembers 5| and 52, are substantially normal to the hydraulic cylinders64. On the application of fluid under pressure to the cylinders 54, toprovide for an upward pivotal movement of the lift frame 33, the rollers59 at the front ends of the lift arms are moved forwardly on thetelescoping members IE to initially elevate the booms IE to theirpositions in a substantially horizontal plane, illustrated in full linesin Fig. 1.

During this initial upward movement of the booms I6 from their dottedline positions A to their horizontal full line positions, the uprightlevers H are pivotally moved rearwardly from their dotted line positionsA to their full line positions also'illustrated in Fig. 1. This rearwardpivotal movement of the levers 11 is accomplished by the downwardpivotal movement of the roc: arms 72 from their dotted line positions ARto their full line positions, illustrated in Fig. 1. The lin 's 83,during this initial elevation of the booms I6, are maintained stationaryby virtue of the action of the lost motion mechanism 81.

As a result the booms l8 are in contracted positions for their upwardpivotal movement from the r dotted line positions A to their full linepositions, so that the scoop 32 at a load carrying position, as definedby the horizontal position of t e booms i6, is ma ntained closelyadia-cent to the forward end of the tractor. As best appears in Fig. l,a horizontal position of the booms 86 takes place when the rock arms 12are in longitudinally aligned positions with the links 83, which alignedpositions define the closest approach of the rear ends of the rock arms72 to the upright levers H in the pivotal movement of the lift frame 33.

On a continued upward movement of the booms !6 from their full linepositions to their dotted line positions, illustrated at C, the rockarms 12 move downwardly and forwardly in a pivotal path providing for aforward pivotal movement of the levers 11, which in turn act to move thelinks 19 in a forward direction. Due to the forward movement of thelinks 19 the telescoping members It! are extended forwardly from theboom rear members I! so that the booms are extended concurrently withtheir elevation from their full line positions to their dotted linepositions C.

During this extension of the booms 16, the lift arms are pivotally movedforwardly and upwardly so that the movable support of the rollers 55with the telescoping members l8 progresses in a direction forwardly ofthe booms Hi. In other words, the rollers 59 are in supporting positionsrelative to the telescoping members l8 such that the rollers 59 aremaintained substantially at the same distance rearwardly of the scoop 32for all elevated positions of the booms [6. A rigid support of the scoop32 for all elevated positions thereof is thus accomplished, so as toeliminate what may be termed a freeswinging load at the front ends ofthe booms l5.

Further, since the supporting arms 58, for the rollers 59, are disposedat opposite sides of the telescoping members [8, the booms iii aremaintained against swinging movement laterally of the tractor. Also,with the lift frame 33 pivoted on the upright frame 36 at a positionintermediate the front wheels I I and rear wheels I3 of the tractor, andwith the support of the hydraulic cylinders 64 rearwardly of the uprightframe 36, the complete weight of the loader attachment, and the weightof the load carried in the scoop 32, is distributed over the tractor ina manner to substantially reduce any overloading of the small tires forthe front wheels I I.

Because of the pivotal connection of the pistons 69, for the cylinder64, with the lift arms at positions intermediate the ends of the liftarms, only a small movement of the pistons is required to pivotally movethe lift frame 33 from its dotted line position LA to its dotted lineposition LC, illustrated in Fig. 1. As a result the pistons 69 are infull bearing support with the cylinders 64-for all elevated positions ofthe booms IS.

The latch mechanism for releasably holding the scoop 32 in a loadcarrying position includes a rock shaft liil (Fig. 4) rockably supportedin bearings I02 and I53 mounted on the top of the transverse connectingmember 29 and a telescoping member I8, respectively. An upright latchI03 mounted on the inner end of the rock shaft IOI has a slotted openinI34 adjacent to its free end which is adapted to receive in lookingengagement a catch member IE6 extended rearwardly from the back wall I31of the scoop 32.

The latch I03 is yieldably maintained in engagement with the catch I06by a torsion spring I03 mounted on the rock shaft IilI, which has oneend I09 engageable with the connecting member 29 and its opposite endIII engageable with the rear side of the latch I03.

An upright rock arm I I2 mounted on the outer end of the rock shaft Isl,has its free end pivotally connected with the front end of a link II3,the rear end of which is pivoted to an upright pivoted lever H4pivotally supported on a link member I9 (Figs. 1 and 2). A second linkH6 is pivotally connected between the upright lever III and a pivotedhandle I I1 carried on the link I9 adjacent to its rear end and at aposition conveniently accessible to the tractor operator.

To dump the scoop 32, the handle H1 is pulled rearwardly whereby thelatch I03 is moved rearwardly against the action of the sprin I08 out ofan engaged position with the catch I06. The scoop 32 i returned bygravity to its load carrying position by virtue of its assembly on the Ipivots 3| in a manner such that when empty its rear end overbalances thefront end thereof.

From a consideration of the above description it is seen that theinvention provides a loading machine which is of a simple and ruggedconstruction, and capable of rigidly supporting a load at all elevatedpositions of the load.

The leader is adapted to initially lift a scoop to a load carryingposition closely adjacent to the front end of the tractor, and then tomove the load forwardly ahead of the tractor on a continued elevation ofthe load lifting arms. The attachment is relatively assembled with thetractor such that full visibility to the tractor operator and a completemaneuverability of the tractor is accomplished for all operatingpositions of the loader.

Although the invention has been describedwith respect to a preferredembodiment thereof, it is to be understood that it is not to be solimited since changes and modifications can be made therein which arewithin the full intended scope of this invention, as defined by theappended claims.

We claim:

1. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged. at opposite sides of said portable framehaving telescoping front members, first means pivotally supporting therear ends of said booms on said portable frame, a load carrying unitmounted between the front ends of said telescoping members, a pair offorwardly extended lift members, second means pivotally supporting therear ends of said lift members on said portable frame at a positionspaced forwardly and above said first supporting means, means at thefront ends of said lift members for movably supporting said booms,rearwardly extended rock arms mounted on said second supporting meansfor movement with said lift members, means for raising and lowering saidlift members, means for moving said telescoping members in response to apivotal movement of said lift members including upright levers on saidfirst supporting means, first links connected between said upright Ilevers and the free ends of said rock arms, and

second links connected between said upright levers and said telescopingfront members.

2. A loading machine including a portable frame, a pair of pivotedtelescopin booms arranged at opposite sides of said frame having fronttelescoping members, means pivoting the rear ends of said booms on saidframe, a load carrying unit mounted between the forward ends of saidtelescoping members, an upright transverse frame on said portable framelocated forwardly of the rear ends of said booms, a pair of lift memberspivotally supported at thei rear ends on said upright frame and havingtheir front ends in a movable and supporting engagement with saidtelescoping members, rearwardly projected extensions on said liftmembers, means for pivotally moving said lift members to raise and lowersaid booms, means for moving said telescoping members in response to apivotal movement of said lift members including a pair of upright leverspivoted on the pivot means for the rear ends of said booms, first linkmembers movably connected between said upright levers and the rear endsof said extensions, and second link members movably connected betweensaid upright levers and said telescoping members.

3. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said frame having fronttelescoping members, means pivoting the rear ends of said booms on saidportable frame, a load carrying unit mounted between the front ends ofsaid telescoping members, an upright frame on said portable framearranged forwardly of said pivot means, a lift frame rockably supportedon said upright frame for up and down pivotal movement including a pairof forwardly extended lift arms having their front ends adapted tomovably engage and support said telescoping members, means for rockingsaid lift frame to raise and lower said lift arms, means for moving saidtelescoping members in response to a pivotal movement of said lift frameincluding rearward extensions on said lift arms arranged so as to beinclined downwardly and rearwardly when said lift arms are in theirlowermost positions, upright levers pivoted at their lower ends on saidpivot means, first links pivotally connected with the rear ends of saidextensions and with said levers intermediate the ends of said levers,and second links pivotally connected between said telescoping membersand the upper ends of said upright levers.

4. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said portable framehaving front telescoping members, means pivoting the rear ends of saidbooms on said portable frame, a load carrying unit mounted between thefront ends of said telescoping members, an upright transverse frame onsaid portable frame located forwardly of said pivot means, a pair ofpivoted lift arms having their rear ends pivotally support on saidupright frame and their frontends adapted to movably engage and sup-portsaid telescoping members, means for pivotally moving said lift arms toraise and lower said booms, means for moving said telescoping members inresponse to a pivotal movement of said lift arms including rearwardlyprojected extensions on said lift arms, a pair of upright levers havingtheir lower ends pivoted on said pivot means, rod members connectedbetween said telescoping members and the upper ends of said uprightlevers, and lost motion means connected between the rear ends of saidextensions and said upright levers to provide for said extensions beingsubstantially normal to said upright lever when said booms are in asubstantially horizontal position,

5. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said frame and pivotedattheir rear ends on said frame said booms having front telescopingmembers, a load carrying unit mounted between the front ends of saidtelescoping members, an upright transverse frame carried on saidportable frame, a pivoted lift frame pivotally supported on said uprightframe and including a pair of forwardly extended lift arms, adjustablemeans supported on the front ends of said lift arms for movementlongitudinally of said lift arms to adjusted positions, means on saidadjustable means for movably engaging and supporting said telescopingmembers, means for swinging said lift frame to raise and lower saidbooms, means for moving said telescoping members in response to aswinging movement of said lift frame including rear extensions on saidlift arms, upright levers having their lower ends pivoted on saidportable frame adjacent to the rear ends of said booms, and link membersmovably connected with said upright levers and with said telescopingmembers and rear extensions.

6. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said frame having fronttelescoping members, a load carrying unit mounted between the front endsof said telescoping members, means for pivoting the rear ends of saidbooms on said portable frame, an upright transverse frame on saidportable frame, a pair of transversely spaced lift members pivotedintermediate their ends on said upright frame, means at the front endsof said lift members for movably engaging and supporting saidtelescoping members, means for swinging said lift members to raise andlower said booms, means for moving said telescoping members in responseto a swinging movement of said lift members including upright leverspivoted at their lower ends adjacent to the pivot means for said booms,first links con- Cir nected between said upright levers and saidtelescoping members, and second links connected between said uprightlevers and the rear end portions of said lift members, with said rearend portions being adapted to be in longitudinal alignment with saidsecond links when said booms are in substantially horizontal positions.

7. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said portable framehaving telescoping front members, first means pivotally supporting therear ends of said booms on said portable frame, a load carrying unitmounted between the front ends of said telescoping members, a pair offorwardly extended lift members, second means pivotally supporting therear ends of said lift members on said portable frame at a posit-ionspaced forwardly from said first supporting means, means at the frontends of said lift members for movably supporting said booms, rock armsmounted on said lift members for pivotal movement therewith, means forraising and lowering said lift members, means for moving saidtelescoping members in response to a pivotal movement of said liftmembers including upright levers pivoted on said portable frame atpositions adjacent to said first supporting means, first links connectedbetween said upright levers and the free ends of said rock arms, andsecond links connected between said upright levers and said telescopingfront members.

8. A loading machine including a portable frame, a pair of pivotedtelescoping booms arranged at opposite sides of said portable frame andpivotally supported at their rear end on said portable frame, said boomshaving front telescoping members, a pair of forwardly extended liftmembers pivotally supported at their rear ends on said portable framefor up and down movement, rock arms onsaid lift members for pivotalmovement therewith, said lift members having their front ends in movablesupporting engagement with said telescoping members, means for pivotallymoving said lift members to raise and lower said booms, means for movingsaid telescoping members in response to an up and down movement of saidlift members comprising first links pivoted at one of their ends to saidfront telescoping members, levers pivoted at one of their ends to saidportable frame, means pivotally connecting together the other ends ofsaid links and levers, and second links movably connected to said rockarms and to said levers.

ERIC M. MCELHINNEY. THEODORE A. PODHAJSKY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,080,461 Cope May 18, 19372,126,791 Low Aug. 16, 1938 2,287,375 Ford, Jr. June 23, 1942 2,295,917schwan Sept. 15, 1942 2,404,820 Wuertz et al July 30, 1946 2,454,461Knapp Nov. 23, 1948 2,465,476 Pokorny et al Mar. 29, 1949

